September08.html

University of Virginia Health
System

Nutrition Support E-Journal Club

September 2008

Greetings,

We enjoyed a brief hiatus from our e-journal club in July and August
due to teaching opportunities with new residents, new GI fellows and
even some vacation fun. We are back on schedule and had a great
September traineeship with trainees from Wilmington, De and Salinas,
CA.

This was a prospective, observational study carried out as part of
the German Competence Network Sepsis (SepNet). Data was collected
from 454 ICUs in 310 hospitals that were visited in a random manner
throughout a year. A cross-section of patient data was obtained
by the collection of 24-hours of data from each hospital.

In total, 3,877 patients were screened with 415 patients found to
have severe sepsis or septic shock, and data was evaluated on 399
patients with sepsis or septic shock that had complete nutrition
information. Hospitals were stratified by size:

¨ University hospitals (n = 10, 3.2%),

¨ University-affiliated hospitals (n = 106, 34.2%),

¨ General hospitals (n = 173, 55.8%)

¨ Others (n = 21, 6.8%).

Information collected included demographic data (age, gender,
weight, height), main diagnoses, co-morbidities, and severity of
illness (Acute Physiology and Chronic Health Evaluation [APACHE] II,
Sepsis-related Organ Failure Assessment [SOFA] score) as well as
diagnostic and therapeutic measures, including nutrition. Total length
of ICU and hospital stay (LOS) as well as hospital mortality was
assessed after 3 months.

The investigators conducted multivariate analysis to identify
factors associated with receiving exclusive enteral nutrition (EN) and
to control for factors such as sepsis, severity of illness, hospital
size, length of ICU stay, and clinical diagnosis expected to influence
the route of nutrition support. In addition, multivariate
analysis was used to analyze the association of the type of nutrition
(enteral, parenteral or combined) with mortality.

Inclusion and Exclusion Criteria were:

Inclusion criteria were adult patients with sepsis or
septic shock that had complete nutrition information for the 24 hour
data period for that hospital.

Exclusion criteria were patients < 18 years, those
without sepsis and those who did not have complete illness or nutrition
data available.

Major Results reported by authors:

Overall, 20.1% of patients received only EN, 35.1% received only
parenteral nutrition (PN), 34.6% received mixed PN + EN (MIX) and 10.3%
of the patients received no nutritional support.

Patients with mechanical ventilation (OR, 0.48; 95% CI, 0.26-0.91),
a GI/intra-abdominal disease (OR, 0.24; 95% CI, 0.11-0.53), and the
presence of septic shock (OR, 0.31; 95% CI, 0.16-0.61) were less likely
to receive exclusively EN. In those patients without any
GI/intra-abdominal disease, exclusive EN was used only 25.9% of the
time. Mean glucose concentration was not significantly different
between the groups, although the MIX group required significantly
increased insulin dose (p = 0.0002).

The authors concluded that their survey reflected a high rate of PN
in patients with severe sepsis or septic shock in German ICUs, and that
PN was associated with increased mortality. They also recommended
randomized controlled trials on the benefits and risks of nutrition
support in the septic population, and suggested that EN could utilized
in a greater percentage of this population.

Evaluation:

This was an ambitious study, which collected data from a large
number of hospitals and patients. Although 24 hours of data
collection may not be representative of practice at a single hospital,
random visits to a large number of centers over a year does should
provide a reasonable cross-section of practice in a broader
sense. The primary limitation of this study is that, as an
observational study, it can only described associations.
Regardless of statistical controls these associations should not be
used to imply cause and effect, but should only allow formation of
theories that need to be tested in randomized studies. Other
limitations of this study, which the authors outline in the discussion
section were: 1) a lack of information on timing of nutrition, 2) the
amounts of nutrition provided, and 3) the prior nutrition status of
patients.

One factor that distinguishes this survey from most done previously,
was the relatively tight glucose control in all groups. The fact
that PN is associated with increased mortality, even in the setting of
tight glucose control suggests that PN
could play a role in increased
mortality. However, as we have already said, there is no way to
completely account for the selection bias that is inevitable in an
observational study of this nature, and randomized studies are
needed. Until these randomized studies are conducted, it is
unlikely that this is the final chapter in the PN versus EN
controversy.

The group felt that the primary benefit of this survey was to draw
attention to the current practice that many patients that could, or
should, receive EN actually still receive PN. At the very least,
the use of PN in patients that could be nourished with EN is not cost
effective, and justifies the need for education of clinical staff, and
implementation of protocols that improve the use and delivery of
EN.

Our Take Home message:

PN is associated with increased mortality in German ICU's, even in
the setting of good glucose control. Randomized studies are
required before any cause-and effect conclusions can be formed
regarding this association.

Other News:

Our next Weekend Warrior 2 day mini-traineeship program is scheduled
for Saturday and Sunday, March 7th &
8th, 2009. If you know anyone who might
not be able to get away for our full week traineeship, please let them
know about our weekend program-there is one scholarship available to
cover tuition also; contact Stacey McCray for details: sf8n@hscmail.mcc.virginia.edu.

Also, coming soon...Nutrition Support
webinars! Keep checking the website for more
information or contact Stacey McCray (sf8n@hscmail.mcc.virginia.edu)
if you would like to be contacted when more information is
available.